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I'm looking for a good roller cam for a 460? Motor is being built for a torino cobra clone. I prefer a hyd. roller with plenty of lift and a moderatly aggressive idle. Compression will be 11.5-12:1,with cobra jet (cast iron) heads, C-6 automatic, and 4.10-4.56:1 rear gears. Car will be street driven, but will also see some strip use. Any suggestions will be appreciated. Thanks.
 

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The solid roller cam and lifters will be about the same cost but will make more power throughout the powerband. The Comp Cams 300AR solid roller sounds perfect for what you want. It is a solid street roller cam with soft lobe ramps, doesn't require a very stout spring, and the RPM range is 3200-6500RPMs which works great with the large CJ/SCJ ports. It will live on the street which is what it's designed for and have a moderate idle. Minimum 10:1 compression and 3500 stall. I am going to use one in my 466 with ported alum CJ heads, 13:1 compression(if I can get it that low), Dominator, 3500 stall, C-4, and 3.89 gears. I know it will make more torque than the car can handle but that's the reason for it. Mild combo with a lot of torque to allow me to tune the suspension to handle it. Then I can set the 557 in there and know the suspension is halfway tuned for the power. Super mild cam, very streetable, non aggressive idle compared to many hydraulic cams, and very reliable. I wish I could get compression down a little more to 12.5:1 but I don't think that's possible with my combo. Hope that helps you out some.
 

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The only problem I see with the 300AR cam is that it's a single pattern stick. CJ head even when ported will seldom have exhaust flow exceeding 60% of the intake side. They really can use some extra duration on the exhaust lobe to help with cylinder scavenging and top end power. I'd recommend one of Comp Cams newer Extreme Energy Roller cams. They are designed for street and strip use. The XR286R (248-254 @.050 .664-.671 110 L/S +4) has less duration on the intake with slightly more lift and runs a tighter lash. Plus it has more duration on the exhaust side. It's interesting that even though the 286 cam has 14 less degrees of duration at the seat than the 300 cam, it only has 9 less at .050 and at .200 lift they are both the same. The XR286 should make at least as much power as the 300AR but it should be more streetable and produce more low end torque.
 

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YUP! This is the cam I got from Greg Cook and I remember him saying he wanted to at least have somewhat of an intimidating idle compare to the 300AR in the 514 in his new 557 but was very disappointed to find the new larger cam in the 557 sounds basically the same... a non intimidating idle
At least it isn't over cammed as much as it's under cammed. There are poeple on the network 54 385 series forum who are using the 300AR solid roller in their 466s and 472s and really like it. I know the Extreem Energy lobes are more aggressive with less duration and will make more power but with more aggressive lobes comes quicker wearing valve springs if putting a lot of street miles but that wouldn't bother me at all. Single pattern cam isn't as important to me because my exhaust port flow will be 60% and over with at least 250CFM exh and 375-390CFM intake flow with little exhaust restriction. Even unported, the alum CJs have a 62.5% int to exh at 200CFM exh and 320CFM intake. Greg Cook's 557 has 13.5:1 compression and small for the cubic inch/RPM 2" primaries and full exhaust so the 270/278 at .050 cam he has should work better than a single pattern cam because of the exhaust restriction. I will have the same 2" primaries and full 3 1/2" exhaust but with only 466 cubes it isn't restrictive enough to worry about having more duration on the exhaust with flow % at 60 or above. I am not one to limit the head potential by just porting the exhaust ports to the max and just clean up the intake ports. That is still limiting power even though it offers a higher exhaust to intake %. Instead, I make the intake port flow as much as possible and then make the exhaust port flow as much as possible and let the percentages fall where they will even if under 50% because more power will be made from increasing flow of the intake port even if the exhaust port flow sucks and is less than 50%. Intake flow gives/makes power, exhaust restriction uses power to expel the gasses. I would rather have 50CFM increase on an intake port than the same 50CFM on the exhaust port because that added intake port flow will make 3 times more power than the increased flow exhaust port. When I build my 557, I will be forced to use the same 2" primary headers and 3 1/2" exhaust even though the cubic inches will be nearly 100 more and at least 13.5:1 compression if not more and at that point I will have to use a dual patern cam with 10 degrees more duration on the exhaust at .050". I have seen some older NHRA ProStock cam grinds showing less lift AND duration on the exhaust (500CID) and I saw a Pro Stock Truck grind the same way(lobes were huge on the intake) and that says a lot. OOPS, I accidentally started going on and on again. I don't even remember what the topic was now. DOH!
 

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I know what you mean Coupe. It's stupid to limit intake flow to make the intake and exhaust ratio ideal. If I could get an intake port to flow so well that the exhaust was only at 40%, I'd do it and just get a custom cam ground that opened the exhaust valve 10 or 15 degrees early. Power on a set up like that would be way up when compared to an engine with an intake port left stock to get the intake/exhaust flow ratio perfect. I was using flow figure from stock CJ iron heads when I reffered to exhaust flow being under 60%, and not the aluminum CJ heads which do have a far better exhaust port. Still 62.5% is far from ideal. Usually 75% to 80% is considered optimum. I'd be inclined to use a dual patter cam profile even with the aluminum CJ heads, especially if the engine is going to see some street duty and can't be really radicle. Just my opinion though....
 

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I agree, the stock CJ exh ports are terrible and can be helped with more duration. 75%-80% is for street cars with OK exhaust systems to be optimum but for more serious street engines and race engines where good headers and large exhaust system is used a 60%-70% ratio is ideal and the 60% rule is for very good scavenging headers with complimentary exhaust systems that can suck the exhaust from the port and cylinder whereas the 70% rule is for free flowing headers that don't really have the good scavenging or too large primaries that don't scavenge good enough at the lower RPMs that the engine is running at. If headers are optimum sized primaries and collectors, then scavenging will be strong and the 60% flow ratio will be right with a symetrical lobe cam(same intake/exh dur). I do like more lift on the exhaust if possible and easy to do just by buying 8 higher ratio rockers to put on the exhaust but then again I also want the most intake lift too because of the added flow benefit. The single pattern cams do idle better and offer more torque low and midrange compared to dual pattern cams plus more vacuum because of less overlap from not using the larger exhaust lobes. Exhaust and headers that are a little too big for the engine/RPM range will want more exh to int % in order to use the single pattern cam for the most power but it seems everybody thinks every engine no matter how well the exhaust port and exh system is needs a dual pattern cam favoring the exhaust. If Greg Cook had an Extreem Energy solid roller grind, I would be even happier to get it from him but the 300AR is a good cam for my combo and has gentle non aggressive lobes which will make my springs wonder if thier even being used with .663 lift.

I know there is a point where increased intake port flow will not gain anymore power with flow increases when exh to int flow reaches 25% or so but few heads are that bad even fully ported on the intake and untouched exhaust.
 

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Realistically though, very few exhaust systems are optimum. Almost all headers that are not full race headers designed for an open type chassis are a compromise, and headers for a big block in a full bodied car are generally the worst of the lot.
 

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Yeh, the big block Fords really got **** on by the header gods. The Chevy's got all the good headers and engine compartments. Just makes it that much harder to make the Fords run but some still do and that is a small ray of hope in this dismall time. At least the big blocks are catching on strong and the aftermarket is responding finally. Ford and their idiotic ideas about shock towers being better, just not for performance. Then designing the engines around the space limited engine compartments and making those absolutely crappy exhaust ports just so it will fit in those engine compartments. Ford really shot themselves in the foot on that one.
 

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Front wheel drive. Ford was high at the time and wanted to try something stupid by the sobered up just in time.
 
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